Arctic sea ice maximum hit a record low in March 2017. Arctic sea ice covered less area than it has any other year since satellite records began in 1979. This record low is the newest in a three-year string of record low Arctic sea ice maximums.
Sea ice grows and dwindles with the polar seasons. Arctic sea ice minimum extent, when Arctic sea ice covers the least area, occurs at the end of the melt season in September. Arctic sea ice maximum extent is measured when sea ice area is at its largest, in March.
The record low sea ice seasonal extent was reported by the National Snow and Ice Data Center (NSIDC). NSIDC performs analysis based on data from the National Oceanic and Atmospheric Administration (NOAA) and from the National Aeronautics and Space Administration (NASA). Mark Serreze, director of the NSIDC, commented on beginning a melt season with low sea ice area: “We’re starting melt season on very, very bad footing.”
March 2017’s Arctic sea ice extent maximum measured 5.57 million square miles (14.42 million square kilometers), smaller than 2016’s maximum of 5.606 million square miles (14.52 million square kilometers) and 2015’s maximum of 5.605 million square miles (14.517 million square kilometers).
The poor showing was not unexpected; the Arctic sea ice minimum in September 2016 tied with September 2007’s minimum for the second lowest yearly minimum extent in the satellite record.
Sea ice growth in fall was slowed due to the unprecedented warm air temperatures in 2016 in the Arctic. Arctic temperatures during the 2016 calendar year were the highest recorded in the temperature record beginning in 1900. NOAA reported: each of the past four years was among the top 10 warmest on record.
Meteorologist Richard Thoman, NOAA National Weather Service Alaska Region, said, “This winter was cold by today’s climate standards.” He continued, “By historic standards, it was completely uninteresting. I’m ready to say beyond any doubt that interior Alaska simply does not experience the temperatures it did in the past.” (February 2017 NOAA news release)
NOAA announced the release of their yearly Arctic Report Card at the annual American Geophysical Union fall meeting in San Francisco in December 2016. Jeremy Mathis, director of NOAA’s Arctic Research Program and report card co-editor, stated: “Rarely have we seen the Arctic show a clearer, stronger or more pronounced signal of persistent warming and its cascading effects on the environment than this year.”
The Arctic, where the impacts of global warming are highly visible, has been called the canary in the coal mine for climate change. Donald Perovich, Adjunct Professor of Engineering, Thayer School of Engineering, Dartmouth College, served as the lead editor for the Sea Ice essay in NOAA’s 2016 Arctic Report Card. He explained, “Arctic air temperature continues to increase at double the rate of the average global temperature.”
“A persistent warming trend in air temperature over the Arctic is driving the changes that we are observing,” Perovich said. In terms of Arctic sea ice cover, he stated: “Back in the 1980s the September ice extent was around the size of of the continental United States. If we look at this past year, 2016, it’s as though part of the United States has melted: the entire United States east of the Missisippi, plus the states from Minnessota all the way down to Louisiana, plus all of North Dakota. So the changes are significant. The changes are real.”
Arctic sea ice is impacted by global temperatures. Warmth sneaks north. Circulating warm Atlantic water reaching Arctic continental shelf seas caused unusually warm fall sea surface temperatures in the Barents and Kara Seas in late 2016, slowing ice formation.
In turn, the widespread presence—or absence—of Arctic sea ice helps regulate global temperatures by influencing oceanic and atmospheric circulation. What is the future of Arctic sea ice?
Laura Nielsen 2017
Frontier Scientists: presenting scientific discovery in the Arctic and beyond